20 Gael Bovallius, 



5. Synopia angustifrons. DANA, 1852. 



(PI. II, «g. 36—39, copied from Dana). 



Sjn. 1852. Synopia angustifrons. DANA. United States Exploring Expedi- 



tion. Crustacea, vol. 2, p. 998, 

 pi. 68, fig. 8 a— d. Fol. 

 1863. „ „ ,, Spence Bate. Catalogue of the specimens of 



Amphipodous Crustacea in of the 

 collection of the British Museum, 

 p. 342, pi. 54, fig. 2. 



Diagn. Caput angustum, trianguläre, longius quam latius. 

 Oculi supplementarii desimt. 

 Aiitennce primi paris quam pereion multo breviorcs; flagellum secunclarium 



longitudiue articulum primum flagelli (veri) sujjerans. 

 Segmentum primum jjerew" secundo brevius, segmentum sextimi et septimum 



sequalia. 

 Femora paris quinti pedum pereii angusta^ rectangularia, femora paris sexti 



duplo latiora, infra truncata; pedes septimi paris jjedibus sexti breviores. 

 Pedunculi pedum plei infra lati, truncati. 

 Segmentum primum uri secundo paulo longius. 



The head is narrow, triangular, longer than broad. 



Secondary eyes are wanting. 



The first pair of antennce are much shorter than the pereion; the 

 secondary flagellum is longer than the first joint of the true flagellum. 



The first pereional segment is shorter than the second; the sixth 

 is as long as the seventh. 



The femora of the fifth pair of pereiopoda are narrow, rectangu- 

 lar, those of the sixth pair twice as broad, truncated below; the seventh 

 pair are shorter than the sixth. 



The peduncles of the pleopoda are broad at the lower ends, truncate. 



The first ural segment is only a little longer than the second. 



The sides of the head »converging forward at an angle of 40" — 50°». 



»The number of ocelli is between 40 and 50.» 



The first pair of antennce [PL II, fig. 38] reach to the anterior 

 margin of the fifth pereional segment, the true »flagellum is five-jointed», 

 the secondary flagellum »three-jointed». 



The second pair of antennae reach beyond the anterior margin of 

 the last pleonal segment. »The flagellum is ten-jointed, joints slender, 

 cylindrical». 



